Experience
Leading the scaling of Adyen's core payment ledger, the system that processes and serves all transactional and accounting data, handling up to 199k transactions per minute in 2025. Work spanned hardening distributed locking, building migration tooling for queue-like workloads later adopted by other teams, leading the internal database framework for real-time connection tuning and query observability, supporting datacenter rollouts through controlled experiments, and performing capacity planning through stress testing and performance analysis, mentoring others in profiling and telemetry-driven optimizations.
Java
Postgres
Prometheus
ELK
NomadBackend engineer on the In-Person Payments Platform team. Built a multi-region WebSocket platform enabling real-time interactions between payment terminals and backend services for both payment processing and fleet management. Grew the platform from thousands to hundreds of thousands of connected devices while maintaining low-latency and high-availability targets. Designed a stress-test suite that surfaced scaling bottlenecks ahead of forecasted growth, and created a dev environment that accelerated terminal firmware integration and compliance certification.
TomcatKlue's first hire in Amsterdam. Helped establish the company's European Machine Learning office together with early employee. Built a nearest-neighbors deduplication API processing 1M+ documents per day and a pipeline for ingesting and processing product reviews. Upgraded core flows to ElasticSearch 7, which required application changes, setting up Infrastructure, and performing live data migration. Contributed to platform security and resilience (ASVS), through rate limiting, user permissions, and JS Subresource Integrity. Setup Google Cloud infra for Python services: CI/CD, load balancers, TLS, and kubernetes; and changed software delivery process for delivery speed.
Python
Ruby
Flask
Rails
Redis
Docker
KubernetesLed the Data Infrastructure and Machine Learning team during a period of rapid growth. The technical work covered establishing the foundational real-time and batch quality assessment pipelines handling 1M+ crowdsourcing tasks per day, end-to-end data flows from ingestion to reporting, and frameworks to bridge research and production. The role also involved owning the team roadmap, headcount planning to deal with rapid growth, interviewing, and running one-on-ones.
C#
Azure Service Bus
Hive
SparkOne of the first engineers at Defined.ai (then DefinedCrowd), there through the company's growth from 7 to ~150 employees. Worked across the full stack: built the SaaS catalog and pricing backend, helped migrate a monolith to microservices, developed a React web app deployed in 56+ countries with full localization, shipped iOS, Android, and desktop audio data collection apps with offline support + internationalization, and set up CI/CD + Azure infrastructure for ML APIs.
ASP.NET
SQL Server
React
Redux
Swift
TensorFlowWorked in the banking and insurance sectors building enterprise Java applications. Improved performance of daily financial reporting pipeline for a capital markets platform from hours to seconds, proposed and automated the deployment of the entire system, maintained and expanded the integration between the client's systems and a centralized Identity Access Management solution using Active Directory.
MySQLScientific initiation scholarship at INESC-ID for the Green-TM project, at the intersection of Parallel Computing, Autonomic Systems, and Machine Learning. Researched and implemented the first energy-efficient Transactional Memory system using self-tuning techniques steered by machine learning, leading to a publication in the International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS).
C
C++